To better understand the safety property to reproductive and development in human of Qingling-Sibutramine hydrochloride (Ql-Sibutramine), a study of toxic effects/disturbances resulting from treatment from before mating (males/females) through mating and implantation of Ql-Sibutramine in mice were conduc-ted. Ql-Sibutramine was administrated in drink water. A premating treatment interval of 8 weeks for male and 2 weeks for female were done in mice. Treatment was continued throughout mating to termination of males and through implantation for female. The dosages were 32 mg*kg-1*d-1 (1/5 LD50), 2.83 mg*kg-1*d-1, 0.25 mg*kg-1*d-1, and a control group. Assessment of maturation of gametes, mating behavior, fertility, preimplantation stages of the embryo, implantation and toxicity to the parent mice were done. The boby weight lose was observed in the group of 32 mg*kg-1*d-1 in male mice. No other toxic effects in the parent mice and offspring were observed.